Cleanup the duplicates of logs rotation functions

Bug: 32067516
Test: Logs rotated successfully on angler, recovery-refresh/persist tests
passed on an a/b device.

Change-Id: Ie80adf0fa958ad3d7869d2d17f49489666b86c29
diff --git a/rotate_logs.h b/rotate_logs.h
new file mode 100644
index 0000000..809c213
--- /dev/null
+++ b/rotate_logs.h
@@ -0,0 +1,44 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef _ROTATE_LOGS_H
+#define _ROTATE_LOGS_H
+
+#include <string>
+
+#include <private/android_logger.h> /* private pmsg functions */
+
+constexpr int KEEP_LOG_COUNT = 10;
+
+ssize_t logbasename(log_id_t /* logId */,
+        char /* prio */,
+        const char *filename,
+        const char * /* buf */, size_t len,
+        void *arg);
+
+ssize_t logrotate(
+        log_id_t logId,
+        char prio,
+        const char *filename,
+        const char *buf, size_t len,
+        void *arg);
+
+// Rename last_log -> last_log.1 -> last_log.2 -> ... -> last_log.$max.
+// Similarly rename last_kmsg -> last_kmsg.1 -> ... -> last_kmsg.$max.
+// Overwrite any existing last_log.$max and last_kmsg.$max.
+void rotate_logs(const char* last_log_file, const char* last_kmsg_file);
+
+#endif //_ROTATE_LOG_H